SACO, Maine — The father of a Saco man who shot and killed his family members in their beds last weekend says his son was ravaged by alcohol abuse and may have lost his grip on reality as he underwent detoxification.

“Five people are dead, five of the closest people in my world are dead, and it had to do with addiction on both parts,” Joel Smith’s father, Stephen Smith, told WMTW TV.

According to Stephen Smith, his son called him on July 15 to say that his bank accounts were empty and that his wife was in severe withdrawal from an opiate addiction.

“He said, ‘Come and get the kids and I’ll let you know when I want them to come back. I don’t want them to see this,’” Stephen Smith told WMTW.

The elder Smith said he picked up the children and kept them for about a week while Heather underwent treatment. When he took the children home, Joel Smith told his father that he had stopped drinking, but the elder Smith still “knew something wasn’t right.”

Police said earlier this week that Joel Smith was having financial difficulties, and that Heather Smith told a family friend the night of the shooting that her husband had threatened suicide earlier in the week by pointing a gun at his head.

“The only thing I can think of is that he may have been so messed up from the alcohol detox that he thought that was the way to save them,” Smith said of his son.

Stephen Smith said his son loved his family and would never have “willingly” hurt his children.

A funeral for Heather Smith and her three children will take place Monday morning in their hometown of Phoenix, Arizona.

According to an obituary published online by the Shadow Mountain Mortuary in Phoenix, Heather Smith and her children were born in Phoenix and moved to Saco four years ago.